全文获取类型
收费全文 | 718篇 |
免费 | 40篇 |
国内免费 | 37篇 |
专业分类
耳鼻咽喉 | 5篇 |
儿科学 | 51篇 |
妇产科学 | 8篇 |
基础医学 | 63篇 |
口腔科学 | 16篇 |
临床医学 | 99篇 |
内科学 | 184篇 |
皮肤病学 | 6篇 |
神经病学 | 27篇 |
特种医学 | 165篇 |
外科学 | 42篇 |
综合类 | 16篇 |
预防医学 | 22篇 |
眼科学 | 8篇 |
药学 | 45篇 |
肿瘤学 | 38篇 |
出版年
2021年 | 7篇 |
2020年 | 4篇 |
2019年 | 12篇 |
2018年 | 12篇 |
2017年 | 7篇 |
2016年 | 6篇 |
2015年 | 8篇 |
2014年 | 17篇 |
2013年 | 23篇 |
2012年 | 21篇 |
2011年 | 14篇 |
2010年 | 38篇 |
2009年 | 39篇 |
2008年 | 17篇 |
2007年 | 31篇 |
2006年 | 12篇 |
2005年 | 19篇 |
2004年 | 5篇 |
2003年 | 8篇 |
2002年 | 13篇 |
2001年 | 15篇 |
2000年 | 7篇 |
1999年 | 12篇 |
1998年 | 48篇 |
1997年 | 50篇 |
1996年 | 46篇 |
1995年 | 40篇 |
1994年 | 41篇 |
1993年 | 27篇 |
1992年 | 3篇 |
1991年 | 12篇 |
1990年 | 11篇 |
1989年 | 25篇 |
1988年 | 23篇 |
1987年 | 12篇 |
1986年 | 15篇 |
1985年 | 10篇 |
1984年 | 8篇 |
1983年 | 6篇 |
1982年 | 10篇 |
1981年 | 8篇 |
1980年 | 10篇 |
1979年 | 5篇 |
1978年 | 7篇 |
1977年 | 10篇 |
1976年 | 6篇 |
1975年 | 3篇 |
1969年 | 2篇 |
1968年 | 2篇 |
1967年 | 3篇 |
排序方式: 共有795条查询结果,搜索用时 15 毫秒
1.
2.
3.
Digital radiography of subtle pulmonary abnormalities: an ROC study of the effect of pixel size on observer performance 总被引:3,自引:0,他引:3
Forty conventional radiographs with examples of mild interstitial infiltrates and subtle pneumothoraces and 40 normal studies of the chest were selected and digitized, with pixel sizes of 1.0, 0.5, 0.2, and 0.1 mm. Observer performance tests were carried out using receiver operating characteristic analysis. Conventional radiographs and digitized images were compared. The results indicate that, in such cases, diagnostic accuracy increases significantly as the pixel size is reduced, at least to the 0.1-mm level. We conclude that, for digital systems using screen-film or similar image receptors, use of a pixel size substantially larger than 0.1 mm may result in some loss of diagnostic accuracy. 相似文献
4.
PL Macken FRACO FRACS CJ Pavlin FRCS R Tuli MD GE Trope PhD FRCS 《Clinical & experimental ophthalmology》1995,23(3):217-220
Background: Spherophakia is an uncommon diagnosis. This is the first case report of spherophakia evaluated by ultrasound biomicroscopy.
Methods: Ultrasound biomicroscopy is a new diagnostic technique developed by one of the authors and provides images with microscopic resolution of the anterior segment. A patient with spherophakia was evaluated by ultrasound biomicroscopy (Zeiss-Humphrey, 50MHz) before and after YAG laser iridotomy.
Results: Ultrasound biomicroscopic assessment revealed a shallow anterior chamber, a very steep anterior lens curvature, iridolenticular contact, elongated zonules, and an increased distance between the lens equator and the ciliary processes. Angle closure glaucoma was due to a pupil block mechanism. The pupil block was relieved by YAG laser iridotomy.
Conclusions: Ultrasound biomicroscopy is a useful technique to confirm the diagnosis of spherophakia. The pupil block in spherophakia is relieved by YAG laser iridotomy. 相似文献
Methods: Ultrasound biomicroscopy is a new diagnostic technique developed by one of the authors and provides images with microscopic resolution of the anterior segment. A patient with spherophakia was evaluated by ultrasound biomicroscopy (Zeiss-Humphrey, 50MHz) before and after YAG laser iridotomy.
Results: Ultrasound biomicroscopic assessment revealed a shallow anterior chamber, a very steep anterior lens curvature, iridolenticular contact, elongated zonules, and an increased distance between the lens equator and the ciliary processes. Angle closure glaucoma was due to a pupil block mechanism. The pupil block was relieved by YAG laser iridotomy.
Conclusions: Ultrasound biomicroscopy is a useful technique to confirm the diagnosis of spherophakia. The pupil block in spherophakia is relieved by YAG laser iridotomy. 相似文献
5.
6.
7.
8.
Helen Herrman Bruce Singh Hilary Schofield Robin Eastwood Philip Burgess Virginia Lewis Richard Scotton 《Australian and New Zealand journal of public health》1993,17(3):261-266
Abstract: Informal caregivers are the families and other unpaid caregivers in the home who support people of all ages with severe and chronic mental or physical disabilities. Home care of this sort has been increasing over the past 30 years because of the reduced number of beds in hospitals and nursing homes and increased outpatient and community care. Moreover, with an aging population and increasing rates of disability, the demand for family caregiving will continue to rise. This has important implications for the development of health, community service and social policy. At the same time, however, very little is known about the impact such changes are having on the caregivers of various ages and in various circumstances. The Victorian Health Promotion Foundation is funding a research and intervention program in Melbourne to promote wellbeing and prevent ill-health in caregivers. 相似文献
9.
The development of both adenocarcinoma of the jejunum and in situ squamous carcinoma of the oesophagus in an adult coeliac patient is described. Good evidence that adenocarcinoma of jejunum occurs more frequently in patients with coeliac disease has recently become available though this association has been suggested for some time. While oesophageal carcinoma has long been associated with coeliac disease, in situ carcinoma of oesophagus has not been previously described in these circumstances. We feel that the risk of this complication, as calculated from published series, warrants a screening programme for oesophageal malignancy in adult coeliacs. 相似文献
10.
Absence of proteinase-activated receptor-1 signaling affords protection from bleomycin-induced lung inflammation and fibrosis 下载免费PDF全文
Howell DC Johns RH Lasky JA Shan B Scotton CJ Laurent GJ Chambers RC 《The American journal of pathology》2005,166(5):1353-1365
Activation of the coagulation cascade is commonly observed in the lungs of patients with both acute and chronic inflammatory and fibrotic lung disorders, as well as in animal models of these disorders. The aim of this study was to examine the contribution of the major thrombin receptor, proteinase-activated receptor-1 (PAR-1), during the acute inflammatory and chronic fibrotic phases of lung injury induced by intratracheal instillation of bleomycin in mice. Inflammatory cell recruitment and increases in bronchoalveolar lavage fluid (BALF) protein were attenuated by 56 +/- 10% (P < 0.05) and 53 +/- 12% (P < 0.05), respectively, in PAR-1-deficient (PAR-1-/-) mice compared with wild-type (WT) mice. PAR-1-/- mice were also protected from bleomycin-induced pulmonary fibrosis with total lung collagen accumulation reduced by 59 +/- 5% (P < 0.05). The protection afforded by PAR-1 deficiency was accompanied by significant reductions in pulmonary levels of the potent PAR-1-inducible proinflammatory and profibrotic mediators, monocyte chemoattractant protein-1 (MCP-1), transforming growth factor-beta-1 (TGF-beta1), and connective tissue growth factor/fibroblast-inducible secreted protein-12 (CTGF/FISP12). In addition, PAR-1 was highly expressed in inflammatory and fibroproliferative lesions in lung sections obtained from patients with fibrotic lung disease. These data show for the first time that PAR-1 signaling plays a key role in experimentally induced lung injury, and they further identify PAR-1 as one of the critical receptors involved in orchestrating the interplay between coagulation, inflammation, and remodeling in response to tissue injury. 相似文献